The present invention relates to a rail switch particularly for an overhead conveyor system adapted to assume at least two switch positions.
A switch of this type is known from GB Patent No. 1,094,319. In the known switch the switch portion is connected to the first rail by a universal joint having two pivot pins extending perpendicular to one another. One of the pivot pins permits the switch portion to be displaced to the various switch positions, while the second pivot pin permits the free end of the switch portion to be lifted for placing it onto the free end of the rail to which it is to be connected. The universal joint is surrounded by a helical spring provided on the one hand for aiding the required movements of the joint and on the other hand for acting as a running surface for the casters. The smallest possible pitch of the helical spring is limited by the mutual abutment of the spring windings on the inner side of the angle formed by the switch portion in its maximum angled position. As a result, the spring windings extend at mutual spacings on all sides in all other positions of the switch portion. The thus created gaps between the spring windings are additionally widened by the circular crosssection of the spring wire, so that the casters connot roll smoothly over the joint.
It is therefore an object of the invention to improve a rail switch of the type defined above in such a manner that it provides a substantially smooth runway surface for said casters spanning the joint.